Abnormal Electrocardiographic Findings in the Population Older Than 40 Years. Prevalence and Clinical Significance. Results of the OFRECE Study.

INTRODUCTION AND OBJECTIVES

Abnormal electrocardiographic findings are highly common. The aim of this study was to analyze the prevalence of abnormal electrocardiographic patterns in the general Spanish population aged 40 years or older.

METHODS

This subanalysis of the OFRECE study selected a representative sample of the Spanish population aged 40 years or older. Clinical data and electrocardiograms were available in all participants. The electrocardiograms were read centrally. Each electrocardiogram was independently assessed by 2 trained cardiologists and, if there was disagreement, a third was consulted to reach a consensus-based diagnosis. Prior to reading the electrocardiograms, diagnostic criteria were strictly defined for each of the abnormalities analyzed. We analyzed the prevalence and clinical factors associated with cavity enlargement, conduction disorders, repolarization abnormalities, pathological Q waves, atrial and ventricular premature beats, and pre-excitation.

RESULTS

A total of 8343 individuals were evaluated, (mean age, 59.2 years; 52.4% women). Only 4074 (51.2%) participants had a completely normal electrocardiogram. The most frequent abnormalities were nonspecific repolarization abnormalities (16%) associated with coronary heart disease and atrial fibrillation; right bundle-branch block (8.1%) associated with chronic pulmonary obstructive disease; left anterior hemiblock (6.5%) related to hypertension and congestive heart failure; and long PR interval (3.7%), which was associated with coronary heart disease.

CONCLUSIONS

Electrocardiographic abnormalities are very common in the general population aged 40 years or older. Only about half of the population had a completely normal electrocardiogram.